Wet Etching Technology for Semiconductor and Solar Silicon Manufacturing: Part 1 - Fundamentals

Abstract

Wet etching is an important step in the manufacturing of semiconductor and solar wafers and for the production of MEMS devices. While it has been replaced by the more precise dry etching technology in advanced semiconductor device fabrication, it still plays an important role in the manufacture of the silicon substrate itself. It is also used for providing stress relief and surface texturing of solar wafers in high volume. The fundamentals of wet etching silicon for semiconductor and solar applications will be reviewed. Different classes of etchants: isotropic and anisotropic: acid and alkaline will be summarized. Key features and attributes for these different etchants will be presented to give the rationale for the use of a particular etchant for a specific application.